A new divertor concept REVOLVER-D2 that uses metal pebbles as a divertor target has been proposed for the LHD-type helical fusion reactor FFHR-c1. Demonstration of sufficient plasma shielding rate is one of the important issues to show the feasibility of the REVOLVER-D2. For this purpose, an experiment on the plasma irradiation to the metal pebble flow has been conducted in the sheet plasma device TPDsheet-U in Tokai University. Reduction of the ion flux and electron density in the metal pebble flow was observed and it was confirmed that the metal pebble flow can play the role of the divertor target. The measured shielding rate is consistent with the prediction by the model based on the Lambert-Beer-Bouger’s law. Achievement of the shielding rate of > 72 % is expected in the FFHR-c1 using the nozzle with the size of > 310 mm × 310 mm and the pebble flow with the diameter of 5 mm.

对于LHD型螺旋聚变反应堆FFHR-c1，已经提出了一种新的分流器概念REVOLVER-D2，其使用金属卵石作为分流器目标。证明足够的等离子体屏蔽率是显示REVOLVER-D2可行性的重要问题之一。为此，在东海大学的片状等离子体装置TPDsheet-U中进行了对金属卵石流的等离子体照射的实验。观察到金属卵石流中离子通量和电子密度的降低，并且证实了金属卵石流可以起到分流器靶的作用。测得的屏蔽率与基于Lambert-Beer-Bouger定律的模型预测一致。使用尺寸为>的喷嘴，在FFHR-c1中有望实现> 72％的屏蔽率